Facebook CEO Mark Zuckerberg arrives on Capitol Hill in Washington, Monday, April 9, 2018. Zuckerberg testified Tuesday before a joint hearing of the Commerce and Judiciary Committees about the use of Facebook data to target American voters in the 2016 election. (AP Photo/J. Scott Applewhite)

Photo: J. Scott Applewhite / Associated Press

Facebook CEO Mark Zuckerberg’s Tuesday appearance at the U.S. Senate was presumably about Facebook’s plans to protect user privacy in the wake of the Cambridge Analytica scandal. But it quickly became about far more than that.

Many of the senators quickly demonstrated that they didn’t understand Facebook, or the Internet, very well. (There were questions about the difference between Twitter and Facebook and how Facebook makes money. “Senator, we ran ads,” Zuckerberg deadpanned. Others were unclear about the concept of “cookies” that don’t come out of the oven.)

But that did not stop senators from railing against Facebook’s practices, at least to the extent they understood them. They did so in a bipartisan fashion.

A number of senators promised if Facebook couldn’t get its act together, government regulation was imminent.

In his statement and his answers to the senators’ questions, a nervous-looking Zuckerberg aimed to present an apologic, humble demeanor. He strove to seem like a cooperative executive, not a stonewalling one.

“It was my mistake, and I’m sorry,” Zuckerberg said.

He promised more: more app audits, a more proactive role for the company in security and content review, more solutions for serious problems like hate speech. He called fighting political misinformation one of his “top priorities for 2018.”

But the overriding response from the senators was skepticism, and rightfully so.

After all, Zuckerberg has apologized for violations of user privacy plenty of times before — he did so in 2010, for example, after Facebook reached a consent decree with the Federal Trade Commission over privacy standards. The Cambridge Analytica scandal showed how little has changed at the company since then.

Zuckerberg seems to realize that user mistrust and congressional anger is growing. But he still seems to believe that the company’s mission to “connect people all over the world” offers users enough fun and optimism to forgive a disturbing pattern of harm. The hearing gave cause to wonder who to trust: a social-media company with a profit motive to keep sharing our personal information or clueless politicians who might try to regulate it.

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